Hey Tom I think you already answered your own question. They want to leave more fish for the nets. It really makes no other sense to choose not to clip the fish. Here's another intersting note on the same line just different river.
The natives on the Columbia have teamed up with the Idaho fish and game in a similar scandal. They have convinced the Idaho Fish and game dept to release 600,000 smolts in the South Fork of the Clearwater (Idaho) river UNCLIPPED! I just don't get it. Well, I do. This will mean that the fish counters will no longer be able to distinguish hatchery vs. wild and the wild fish run will be artificially increased by hatchery fish. Then the natives can say "the fish are having a good year, so we should be able to take more wild fish this year". But guess who gets the short end of this deal, sportsmen. This will most likely bring higher harvest rates for the natives (and yes other commercial fishermen) yieldiing even lower returns than present now. Do you think an dorsal fin lenght rule will occur here, I think not.
I just saw this in the Lewiston Daily news on Monday. If anyone has any more info on this I would be interested. Info such as the scientific reasoning behind the decision. Only reason they stated in the article was that they are hoping to get more native fish into the SF Clearwater. But I thought that the majority of the management believes that a hatchery fish is genetically different than a wild fish, won't this dilute any existing wild genetic stocks if the hatchery fish do take hold. Isn't this why they halted hatchery production on the upper columbia river tribs like the Wenatchee. Don't hatchery fish have a pitifully low reproduction rate as it is. Why not clip the darn fish and still release them in the same place and hope for some natural reproduction and still allow some sportfisherman the opporitunity to catch the fish they are paying for.

Duke